cos_generate.asm

基于c5000的cos函数发生器

  .mmregs
  .def cos_generate,cosend  ;,end_of_cose
  .def d_cos_delay1,d_cos_delay2,d_theta,d_cosx
  .def begin
  
d_cos_delay1  .usect "cos_vars",1
d_cos_delay2  .usect "cos_vars",1
d_theta       .usect "cos_vars",1
d_cosx        .usect "cos_vars",1


k_cos_delay1  .set  064d8h
k_cos_delay2  .set  06602h
k_cos_theta   .set  07f83h
k_2           .set  2h
k_256         .set  256

COSDATA       .usect "cos_data",256

  .text
  
begin:
  SSBX FRCT
  STM   COSDATA,ar5   ;;;;;;;;;;;;;;;;;;;;;;;;;;
  NOP
  STM  #600H,SP
  LD  #d_cos_delay1,DP
  NOP
  
  
  STM  #d_cos_delay1,ar3
  STM  #d_theta,ar4
  RPTZ A,#3H
  STL  A,*ar3+
  NOP
  NOP
  
  STM  #1,ar0
  STM  #k_2,BK
  STM  #k_256-2-1,BRC
  NOP
  STM  #d_cosx,ar2
  STM  #d_cos_delay1,ar3
  ST   #k_cos_delay1,*ar3+
  ST   #k_cos_delay2,*ar3
  STM  #d_cos_delay1,ar3
  ST   #k_cos_theta,d_cosx
  
  ST  #k_cos_delay1,*ar5+
  ST  #k_cos_delay2,*ar5+
  
cos_generate:
  RPTB  cosend-1  ;end_of_cose
  MPY   *ar2,*ar3+0%,A
  SUB   *ar3,15,A
  SFTA  A,1,A
  STH  A,*ar3
  MVDD  *ar3,*ar5+
  NOP
  NOP
  NOP
;end_of_cose:
;  B    cos_generate
cosend:
LOOP:
   B  LOOP
  .end